Device for transfer of heat

ABSTRACT

A structure for housing electronic equipment, for example outdoor telecom applications such as radio base stations, in a climate-controlled environment. The structure comprises a compact climate-control unit adapted for integration into the structure. The climate system provides for circulation of air in an internal closed circuit for cooling of heat generated by the electronic units within a closed space within the interior of the structure.

This application claims the benefit under 35 USC § 119(e) to Provisional application 60/708,770 filed 17 Aug. 2005 and Provisional application 60/709,133 filed 18 Aug. 2005.

BACKGROUND Field of the invention

The present invention relates to a simplified structure for preferably outdoor telecom applications, e.g. radio base stations. The simplified structure comprises a compact climate system adapted for integration into a fundamental structure for electronics.

BACKGROUND

As will be obvious for a man skilled in the art, the climate system has as a function to transport heat from the inner space of the outdoor cabinet to the outdoor ambient. It need not only be meant for cooling of electronic equipment but all kinds of heat exchange are conceivable.

The invention is a further development of the device described in WO 92/18821, the teachings of which are hereby incorporated by reference.

The conventional structures of today for outdoor cabinets for telecom equipment or other outdoor based electronic systems include electronic units which are often built-in in rack systems, climate systems for cooling of the electronics, channel systems for cooling air and a cabinet housing enclosing said equipment. The climate system requires cleaning of the parts exposed to outdoor air and must therefore be accessible for maintenance. This requirement of accessibility implies distinct limitations as to integrating the climate plant with the electronics. Common climate systems are located along walls, doors or roofs of the cabinet housing. They are thus not included in the structure for the electronics, but form an independent unit.

In the prior art systems, air intended for cooling of the electronics is generally mixed with heated air from the electronics. This leads to a reduction in cooling efficiency and increases the temperature of the air intended for the cooling of the electronics. A temperature increase of air intended for cooling may lead reduction of functions, breakdown in production or damages of the electronics.

To avoid this reduction in heat exchange efficiency some systems are equipped with connecting parts between the electronics and the climate system, and the risk for leakage between the parts is increased. These type of systems are complicated with a lot of tubing, and leakage in these cases will lead to the above mentioned problems.

To avoid said problems associated the climate systems, some climate systems are supplemented with an active cooling portion to ensure the temperatures permissible for the electronics. These types of systems with several parts located in different ways on different portions in the cabinet, which parts simultaneously have to be connected and function correctly together, become very voluminous, require a lot of mechanic parts, are difficult to standardize, require specific adaptation and are expensive.

SUMMARY OF THE INVENTION

The present invention aims at eliminating the above drawbacks. This is achieved by building-in a climate unit according to claim 1, i.e. a structure for outdoor cabinets containing electronic equipment, for instance telecom equipment containing the electronics of fixed standardised systems together with a climate unit for the cooling of the electronics characterised in that the climate unit is integrated in the support structure for the electronics.

The invention comprises also a structure characterised in that the climate unit is located in rack systems together with the electronic units, and particularly a structure characterised in that the climate unit provides a substantially closed circulation of air cooling to and from the electronic units within the outdoor cabinet or a structure for the outdoor cabinet containing a climate unit characterised in that the air from the electronics is transferred within the rack system to the climate unit. The invention also comprises a structure for outdoor cabinets containing an air condition unit characterised in that the climate unit is located on top of the rack system being common to the electronic units, and/or a structure for an outdoor cabinet containing the climate unit characterised in that the climate unit is located in another configuration in the rack system being common with the electronic units.

In one embodiment the invention comprises a structure for outdoor cabinets containing a climate unit characterised in that the climate unit has substantially closed channels for the air flow to and from the outdoor environment and/or a structure for outdoor cabinets containing a climate unit characterised in that air from the climate unit intended for cooling of the electronic unit is transferred from the climate unit through channels between the housing of the rack system and the outdoor cabinet.

In another embodiment the invention comprises a structure for outdoor cabinets containing a climate unit, wherein the climate unit is a rotating heat exchanger adapted for the transfer of heat or mass with the aid of rotating surfaces, as described in the patent application WO92/18821 characterised in that the climate unit is located so that the inlet of the climate unit to the rotating heat exchanger is arranged directly above and in direct connection to the structure for the electronics and/or a structure for outdoor cabinets containing a climate unit, wherein the climate unit is a heat exchanger as described in the patent application WO92/18821 characterised in that the outlet channels of the heat exchanger are common with the natural cavities between the outer walls of the cabinet and the periphery surfaces of the rack system of the structure for the electronics.

The invention comprises also a climate system for an outdoor cabinet containing electronic equipment, the system being adapted for connection to the top of the outdoor cabinet, and comprising a roof, openings for inflow and outflow of air from/to the ambient, a vertical partition plate for separation of an incoming air chamber from an outgoing air chamber, horizontal partition plates for separation of the incoming and outgoing air chambers from the outdoor cabinet's inner space, a compartment comprising a climate unit, the compartment comprising an inlet opening for inflow of air and outlet opening for outflow of air to from the incoming and outgoing air chambers respectively, and outlet and inlet openings in fluid connection with the outdoor cabinet's inner space.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described by means of examples of embodiments of the invention and with reference to the enclosed drawings, of which:

FIG. 1 shows an embodiment in a vertical view perpendicular to the front of the structure, according to the denomination according to telecom standards of structures for electronics, into which the present invention is implemented.

FIG. 2 shows a horizontal view in a section A-A according to FIG. 1 of the structure for electronics with the present invention in a plane above the separation plate 7.

DETAILED DESCRIPTION OF THE INVENTION

In FIG. 1 one embodiment of a structure for electronics in outdoor cabinets, with the present invention implemented, is shown. Said structure comprises an outdoor cabinet 100, a climate unit 5, a collection chamber 4 and electronic units 2 and 3, which components are mounted in a rack system comprising vertical support beams 1 in the outdoor cabinet 100. The outdoor cabinet 100 is formed by a bottom 16, walls 6 and a roof 8.

The climate unit 5 takes an airflow 20 through openings 9 in the climate unit 5. Said air is cooled in the climate unit 5 and exits as air flows 21 through outlet openings 10 of the climate unit. The airflow 21 flows through openings in vertical support beams 1 and into the electronics unit 3 at the bottom of the rack system. Airflow is caused to be distributed into spread flows 22 as it enters unit 3 according to a method known for structures intended for electronics for e.g. telecom. Said spread flows 22 exit the top of unit 3, and are further transferred to the bottom of electronic unit 2, where there is a possibility to redistribution of airflows 22 into further airflows 23. During transfer of airflows 22 and 23 respectively through the electronic units 2 and 3, said flows are heated when they cool available electronic components. The heated air is transferred finally from unit 2 to collection chamber 4, which distributes the suction force from the climate unit 5. The collected air in chamber 4 thereafter can reenter climate unit 5 as airflow 20, thus defining a continuous circuit of airflow. The airflows 21, 22, 23 and 20 constitute a substantially closed, defined air volume separated from the air outside the housing. In FIG. 1 an inflow 24 is shown through openings 11 above two separation plates 7, which inflow consists of ambient air from the outside of the cabinet housing 100. Said air is supplied to the climate unit 5 through openings 13 therein and absorbs in the climate unit heat from the air stream 20 as well as additional heat from power dissipations in the climate unit itself. The heated air stream 25 from the climate unit 5 flows out of the unit through an opening 14 in the climate unit 5 and further into the ambient air. Streams 24 and 25 are separated by a vertical partition plate 15.

FIG. 2 shows the structure according to the invention seen from above, with roof 8 removed. The figure shows walls 6 in cabinet 100, partition plate 15, inlet and outlet openings 11 and 12, inlet opening 9, outlet opening 14. This upper part forms a climate system which is in fluid connection with the inner space 110 in cabinet 100 (FIG. 1) by means of openings 10.

Alternative embodiments of the above structure with a climate unit may of course be found, for instance the collection chamber 4 may be reduced. Further, the flow of cooling air from the climate unit 5 to the electronic units 2, 3 may be implemented in different ways, e.g. in the space between the electronic units 2 and 3 and on the outer side plate 6 of the cabinet.

In addition, climate unit 5 may comprise of heat exchangers as described in patent application WO 92/18821 based on rotating discs with the discs provided substantially perpendicular to the direction of the air flow in the air stream 20 from the electronic units. The heat exchanger's inlet of outdoor ambient air can be connected to opening 9. The heated air stream 20 from the electronic units will then be directed into the inlet of the heat exchanger for the air stream circulating in the cabinet closed circulation system for cooling the electronic units without other mechanical means or complicated channel means. The heat exchanger outlet for the outdoor ambient air 25 on the surface containing the edges of the discs will be connected to the cabinet housing openings 14 and further out through opening 12 and the cooled air stream 21 from the heat exchanger in the inner loop will then land in the channels such as the natural cavities between the outer walls of the outdoor cabinet and the electronic units. 

1. A structure for containing electronic equipment such as electronic telecom units in a controlled climate, comprising an outside cabinet having an internal closed space wherein are located the electronic units such that the electronic units are substantially isolated from the outside environment, and further comprising a climate-control unit that is in air-flow fluid connection with the closed space in which the electronic units are located.
 2. A structure according to claim 1, wherein a rack system for holding the electronic units is provided within the closed space, said rack system comprising vertical support members.
 3. A structure according to claim 2, wherein the electronic units are arranged vertically within the rack system, the climate-control unit is located at the top of the rack system and arranged such that a substantially closed and continuous circuit of airflow is created, such that heated air exits the electronic units, enters the climate-control unit where the air is cooled, and thereafter exits the climate-control unit into the closed space.
 4. A structure according to claim 3, wherein the outside cabinet comprises a top, a bottom and walls, and wherein the vertical support members define cavities between the vertical support members and the insides of the walls of the cabinet, and wherein the outlet of the climate-control unit is in air-flow fluid connection with said cavities, and the air inlet of the climate-control unit is in air-flow fluid connection with the space between the vertical support members wherein the units are located, and further wherein the vertical support members have channels defining air-flow paths from the cavities to the space between the vertical support members, such that air from the climate-control unit enters the cavities, passes through the channels in the vertical support members, passes through the electronic units thereby exchanging heat, and thereafter reenters the climate-control unit in a continuous, substantially closed circuit.
 5. A structure according to claim 4, wherein the electronic units are arranged such that air enters the bottom of a lower unit, passes through the top of said unit and thereafter enters the bottom of the next adjacent electronic unit, and thereafter exits the top of the topmost unit and enters the climate-control unit.
 6. A structure according to claim 1-5, wherein the climate-control unit has closed channels for the transfer of air streams to and from the outside environment.
 7. A structure according to claim 6, wherein the climate-control unit is a rotating heat exchanger located in such a way that the inlet of the climate-control unit to the rotating heat exchanger is arranged directly above and in direct fluid connection with the closed space in which is located the electronic units.
 8. A structure according to claim 7, wherein the climate unit is a rotating heat exchanger where the outlet channels of the heat exchanger are in fluid connection with the cavities between the walls of structure and the peripheral surfaces of the rack system for the electronics.
 9. Climate system for an outdoor cabinet containing electronic equipment, the system being adapted for connection to the top of the outdoor cabinet, and comprising a roof, openings for inflow and outflow of air from/to the ambient environment, a vertical partition plate for separation of an incoming air chamber from an outgoing air chamber, horizontal partition plates for separation of the incoming and outgoing air chambers from the outdoor cabinet's inner space, a compartment comprising an climate unit, the compartment comprising an inlet opening for inflow of air and outlet opening for outflow of air to and from the incoming and outgoing air chambers respectively, and outlet and inlet openings in fluid connection with the outdoor cabinet's inner space. 